//ArraysMem.java
package com.ylaihui.array;

public class ArraysMem {
	public static void main(String[] args) {
		int[][] arr = new int[4][3];
		
		System.out.println(arr[0]);  // [I@15db9742 
		System.out.println(arr[0][0]);  // 0
		
		System.out.println(arr);  // [[I@6d06d69c
		
		int[][] arr2 = new int[4][];  // null
		System.out.println(arr2[0]);
//		System.out.println(arr2[0][0]);  // NullPointerException
		
		String[][] arr3 = new String[4][3];
		System.out.println(arr3[0]);  // [Ljava.lang.String;@7852e922
		System.out.println(arr3[0][0]);  // null
	} 
}
